Want the demon back?

So, the mauler cart. While I've liked the idea quite, I was never 100% satisfied with what it ended up, a one-shot linebreaker. So I decided to change that and mixed it with the rock lobbas, thus giving birth to the bastard child that is:

The Trolley Cart. The idea is still the same, but now the platform has enough room on it to house a catapult and an ork to operate it. The catapult fires small bombs (stolen gunpowder crammed tightly in small containers, which explode on impact, or fanwank something more acceptable if you want realism) to a short range, and the troll is now armed with a pokey stick, with which it can impale nearby opponents who'd try to attack the catapult ork.